Process for the manufacture of barium alkyl phenates



Patented Nov. 6, 1962 3,062,807 PRUCESS FQR THE MANUFAQTURE 9F BARIUM ALKYL PHENATES Carl F. lrutton, New York, N.Y., (Ilarlr (P. Miller, Willoughhy Hills, @lsio, and Loren A. Bryan, Railway, N.J., assignors to FMC tlorporation, a corporation of Delaware No Drawing. Filed Nov. 2, 1959, Ser. No. 850,043 8 Claims. (Cl. 260-624) This invention relates to the manufacture of barium alkyl phenates, and more particularly to the production of barium alkyl phenates from low cost, readily available chemicals.

The barium alkyl phenates, which have found application as lubricating oil additives, insecticides and the like, currently are prepared by reaction of barium oxide with the corresponding alkyl phenol. This is an expensive procedure; the barium oxide employed in the reaction is not available naturally, and is expensive to manufacture. Normally the barium oxide is prepared by reducing naturally occurring barium sulfate to the sulfide, converting the sulfide to barium carbonate, and then decomposing the carbonate at a high temperature to provide barium oxide. As a result of this involved preliminary operation, the previous method of preparing the barium alkyl phenates has been a costly one, and has limited their use.

Attempts have been made to form barium alkyl phenates from inexpensive barium sulfide. However, although barium sulfide reacts with simple phenol to yield barium phenate in excellent yields, the reaction of equimolar quantities of alkyl phenols with barium sulfide proceeds with low efficiency, yields of only as much as 30% to 40% having been obtained. Since recovery of unreacted alkyl phenols fromthe reaction mixture is expensive, this reaction has not been commercially feasible.

it is an object of this invention to provide a process for the production of barium alkyl phenates from low cost, readily obtained, barium sulfide.

It is a further object of this invention to provide such a process which may be operated in simple equipment, and with high yields of product.

It has now been found that barium alkyl phenates can be prepared by reaction of barium sulfide, phenol and an alkyl phenol. Surprisingly, this reaction proceeds with the ultimate formation of barium alkyl phenates in yields as high as quantitative, rather than with formation ultimately of the expected barium phenate. The reason for this conversion to the barium alkyl phenate is believed to reside in the presently discovered fact that barium phenate reacts with alkyl phenols to form barium alkyl phenates and phenol. Barium phenate is formed in situ in the reaction mixture of barium sulfide, phenol and alkyl phenol, and the barium phenate in turn reacts with the alkyl phenol to form the desired product.

In the preferred embodiment of the present process, a mixture of about 1 mole of barium sulfide, about 0.2 to 2 moles of phenol, about 0.8 to 3.5 moles of water and about 2 moles of an alkyl phenol is heated to a temperature of from about 75 to about 160 C., and preferably at about 100 to about 160 C., to yield the barium alkyl phenate, and the barium alkyl phenate is recovered. In this embodiment, the barium sulfide and phenol are believed to react in situ to form barium phenate, which then reacts with the alkyl phenol to form the barium alkyl phenate product.

In another embodiment of the invention, a barium al- 'kyl phenate is prepared by reacting barium phenate with an alkyl phenol at a temperature from about 140 to about 230 C., and preferably at about 180 to about 230 C., and recovering the barium alkyl phenate produced. It is preferred in this embodiment to employ the alkyl phenol in excess over the theoretical amount required for reaction with the barium phenate, suitably up to about 8 moles of the alkyl phenol per mole of barium phenate, although the reaction may be conducted efficiently with the stoichiometric amount, 2 moles per mole of barium phenate, of the alkyl phenol.

The reactions of this invention may be represented by the following equations. The reaction of barium phenate with an alkyl phenol to yield the barium alkyl phenate is shown first, in order that the probable course of Reaction 2, involving in situ formation of barium phenate and reaction thereof with the alkyl phenol, may be clearly understood. J

(Reaction 1) Ba 1 3. 9 0 I (Reaction 2) OH (F11 BaS 2 2 Rn in which n is an integer from 1 to 3, and at least one R group is an alkyl radical having 4 to 20 carbon atoms. Barium alkyl phenates in which any remaining R groups may be alkyl, cycloalkyl, aralkyl, aryl or naphthenyl groups having to 20 carbon atoms, may be prepared by the present method, and provide products which find application as oil additives, insecticides and the like.

Reaction 1, involving the reaction of barium phenate and an alkyl phenol, is carried out at a temperature of about to about 230 C., and preferably at about 180 to 230 C. it normally is substantially completed in about 1 to 3 hours. The reaction preferably is conducted at atmospheric pressure, although it may be run at pressures above or below atmospheric. Operation at about 180 to 230 C. is preferred, because at a temperature above about 180 0., and at the preferred atmospheric pressure, phenol by-product is evolved and the conversion to barium alkyl phenate is favored. When the reaction is conducted at reduced pressures, phenol obviously will be evolved at temperatures below about 180 C., and conversion likewise will be favored. At temperatures above about 230 C., the alkyl phenol tends to volatilize from the reaction mixture at an unduly high rate. While it is possible to operate above 230 C. by returning volatilize d alkyl phenol to the reaction mixture, or by operating at increased pressures, it is preferred for obvious reasons to conduct the reaction at a tempera ture below about 230 C.

he alkyl phenol is preferably employed in about twice the stoichio-metric amount required for displacement of phenol from the barium phenate, for the reason that the reaction proceeds more readily in the presence of an excess of the alkyl phenol. However, it will be apparent that larger or smaller amounts of the alkyl phenol may be employed, it being possible to conduct the reaction with as little as a stoichiometric amount of the alkyl phenol,

Ba OH or with as much as 3 to 4 times the stoichiornetric requirement of it. This means that about 2 to 8 moles of alkyl phenol may be employed for each mole of barium phenate.

Reaction 2 involves the additional feature of preparing the barium phenate, which reacts with an alkyl phenol to form the corresponding barium alkyl phenate, in situ in the reaction mixture. It is believed that the barium sulfide and phenol, in the presence of water, react to form barium phenate and hydrogen sulfide. The hydrogen sulfide escapes from the system, and the reaction to form barium alkyl phenate proceeds. In this case the phenol generated by the reaction between the barium phenate and the alkyl phenol is reacted with barium sulfide in accordance with the reaction described above, and accordingly need not be volatilized from the reaction mixture.

Temperature conditions for Reaction 2 difier from those of Reaction 1. In Reaction 1, phenol is removed as a vapor, and accordingly the reaction preferably is conducted at a temperature of about 180 to about 230 C., temperatures at which the phenol is volatilized. In Reaction 2, since the phenol generated is used as a reactant in the formation of barium phenate, it is desired not to volatilize it fro-m the reaction mixture. Accordingly, the reaction is conducted at a temperature of about 75 to about 160 C., and preferably at a temperature of about 100 to about 160 C. It will be apparent that the reaction may be conducted at higher temperatures, up to about 230 C., provided provisions are made for returning to the reaction mixture, the phenol and other volatiles which are evolved at the higher temperatures, or provided the reaction is conducted at an elevated pressure. The reaction normally will take place in about 3 to 12 hours at the preferred temperatures of from 100 to 160 C. As in Reaction 1, Reaction 2 may be conducted at atmospheric pressure, or at pressures above or below atmospheric. It is preferred to operate this reaction at atmospheric pressure, and at a temperature in the range of about 100 to about 160 C.

The reaction between barium sulfide and phenol proceeds in the presence of water. The amount of water used may vary widely, although use of about 0.8 to 3.5 moles of water per mole of barium sulfide provides for most eflicient operation. The barium sulfide employed may be in the form of so-called black ash, an impure and low-cost barium sulfide produced by reaction of barytes, a naturally occurring barium sulfate, with coal in an air-tight furnace. The product of this reaction contaius on the order of 70% barium sulfide, and is low in cost. Use of this inexpensive starting chemical leads to substantial savings in the production of barium alkyl phenates, and surprisingly does not interfere with efficient operation of the process.

The phenol serves in Reaction 2 both as a reactant and as a catalyst for the reaction between it and the barium sulfide. It is preferred to employ phenol in the amount of about 2 moles per mole of barium sulfide, although as little as 0.2 mole of the phenol can be used for each mole of barium sulfide, since the phenol is returned to the reaction upon being liberated from the barium phenate by the alkyl phenol.

The alkyl phenol preferably is employed in Reaction 2 in the amount of about 2 moles per mole of barium sulfide, although departures from this amount may be made with consequent reductions in the amount of barium alkyl phenate producible from a given volume of reaction mixture.

The reaction mixtures resulting from Reaction 1 and Reaction 2 may be worked up readily by removing the residual phenols and other volatiles as vapors under suitable vacuum and temperature conditions, and thereafter dissolving the barium alkyl phenate product remaining in the reaction mixture in a solvent such as chloroform, or a hydrocarbon solvent such as toluene, mineral oil and the like. Solid impurities such as barium carbonate, carbon, barium silicate and the like may be removed by filtering the resulting barium alkyl phcnate solution. This solution then may be used directly, or the solvent may be removed by distillation to provide the pure barium alkyl phenate product.

The folowing examples are given by way of illustration of the present process only, and are not intended as limitations on the scope of the process.

A. REACTIONS OF BARIUM SULFIDE, PHENOL, ALKYL PHENOL AND WATER Example 1 Two moles (440 g.) of nonyl phenol were introduced into a 3-liter, 3-necked flask, together with 218 g. of black ash analyzing 78% barium sulfide, and containing 1 mole thereof, and 2 moles (188 g.) of phenol. A reflux condenser was fitted to one neck of the flask, a motor stirrer to the center neck, and a thermometer was inserted in the third neck. Heat was applied by means of a Glascol heating mantle. While the reaction mixture was being heated, about 50 cc. of water was added to the flask.

When the reaction mixture reached a temperature of C., an H 8 odor was noted at the top of the reflux condenser; a tube was then connected to the condenser and lead to a caustic trap for absorption of the H S. The

7 reaction mixture was allowed to reflux at about C. for 4-5 hours. At the end of this time, the evolution of hydrogen sulfide had practically ceased.

A vacuum was applied to the reaction mixture in the flask, and water containing a small amount of phenol was distilled oif. One hundred eighty-six grams of phenol was then removed. The maximum temperature reached in the distillation was C., and the lowest pressure was 2 mm. of mercury. Three hundred grams of toluene was added to the reaction product in order to keep the barium nonyl phenate product in solution. This solution was filtered through a Celite pad on a Biichner funnel, to remove the carbon of the black ash.

The toluene was removed from the reaction product, and 573 g. of barium nonyl phenate was obtained. This was a yield of 99% of the barium nonyl phenate, a brown colored, waxy solid. It analyzed 39.3% BaSO ash; theory was 40.5% BaSO ash.

Example 2 Example 3 Dinonyl phenol in the amount of 0.20 mole, 0.20 mole of phenol, 0.10 mole of 85% barium sulfide and 0.25 mole of water were reacted together following the procedure set forth in Example 1. The reaction took place at a temperature between 74 and 131 C., and was completed in 10 hours. Fifty-seven grams of barium dinonyl phenate was recovered. This represents a yield of 69%. The barium dinonyl phenate analyzed 28.5% 132.50., ash; theory was 28.1% BaSO ash.

Example 4 Secondary-amyl phenol in the amount of 0.20 mole, 0.20 mole of phenol, 0.10 mole of barium sulfide and 0.25 mole of water were reacted together following the procedure set forth in Example 1. The reaction took place at a temperature between 72 and 125 C., and was complete in 4 hours. Fifty-five grams of barium nonyl phenate was recovered. This represented a yield of 95% of theory. The barium nonyl phenate analyzed 32.6% BaSO ash; theory was 40.5% B2130 ash.

Example 6 Nonyl phenol in the amount of 0.2 mole, 0.02 mole of phenol, 0.10 mole of barium sulfide of 85% purity and 0.08 mole of water reacted together following the procedure set forth in Example 1. The reaction took place at a temperature of between 110 and 131 C., and was stopped after 4 hours, although some reaction was still apparent from a slow continued evolution of more hydrogen sulfide. Twenty-two grams of barium nonyl phenate was recovered. This represented a yield of 38%. The barium nonyl phenate analyzed 31.6% BaSO ash; theory was 40.5% B3504 ash. This example demonstrates that the reaction may be conducted with a small amount of phenol.

B. REACTIONS OF BARIUM PHENATE WTTH ALKYL PHENOLS Example 7 One mole (391 g.) of barium phenoxide tetrahydrate and 2 moles (417 g.) of octyl phenol were stirred together in a 2-liter, 3-necked flask equipped with a mechanical stirrer and a thermometer. The third neck of the flask was fitted with a tube connected to a cold water trap for recovery of volatilized phenol and any alkyl phenol driven from the reaction mixture during the re action.

The reaction mixture was heated to 190 C., and then over one hour to 220 C. Following this, the reaction mixture was heated at 140 C. and a pressure of 2 mm. of mercury to remove water and residual phenol. Toluone was added to the reaction mixture to keep the barium octyl phenate in solution. The solution was filtered through a Celite pad on a Biichner tunnel to remove solid impurities.

The toluene was stripped from the product, and 353 g. of barium octyl phenate was obtained. This was a yield of 64%.

Example 8 One mole (391 g.) of barium phenoxide tetrahydrate and 2 moles (304 g.) of tert-butyl phenol were stirred together in a 2-liter, 3-necked flask as described in Example 7.

The reaction mixture was heated to 180 C. and then over three hours to a temperature of 225 C. The product of the reaction, barium tert-butyl phenate, was recovered in the amount of 131 g. (30% yield) by the procedure described in Example 7.

Example 9 One mole (323 g.) of barium phenoxide, and 2 moles (444 g.) of nonyl phenol and 100 g. of water were stirred together in a 2-liter, 3-necked flask equipped with a mechanical stirrer and thermometer. The third neck of the flask was fitted with a reflux condenser.

The reaction mixture was heated to 145 C. and thereafter raised to 190 C. over 4 hours. Following this, residual phenol and water were removed from the reaction rnbrture and the reaction product, barium nonylphenate, was worked up as described in Example 7. The yield of product was 507 g., 88% of theoretical.

The barium alkyl phenates are useful in a number of applications. They may be employed as insecticides, as detergents and dispersants in non-aqueous systems, as corrosion inhibitors, as anti-oxidants in oils, leaded gasoline and rubber, and as drying aids in surface coatings. The most extensive application of this class of compounds appears to be in automotive lubricating oils, where they are used to prevent varnish formation on pistons and excessive wear on bearings.

Pursuant to the requirements of the patent statutes, the principle of this invention has been explained and exemplified in a marner so that it can be readily practiced by those skilled in the art, such exemplification including what is considered to represent the best embodiment of the invention. However, it should be clearly understood that, within the scope of the appended claims, the invention may be practiced by those skilled in the art, and having the benefit of this disclosure, otherwise than as specifically described and exemplified herein.

That which is claimed as patentably novel is:

1. Process for preparing a barium alkyl phenate, comprising reacting barium phenate with an alkyl phenol selected from the group consisting of monoalkyl phenols and dialkyl phenols at a temperature of about 140 to about 230 C. until a barium alkyl phenate is produced, and recovering said barium alkyl phenate.

2. Process of claim 1 in which the temperature of reaction is from about 180 to about 230 C.

3. Process for preparing a barium alkyl phenate, comprising reacting about 1 mole of barium phenate with about 2 to 8 moles of an alkyl phenol selected from the group consisting of monoalkyl phenols and dialkyl phenols at a temperature of about 140 to 230 C. until a barium alkyl pncnate is produced, and recovering said barium alkyl phenate.

4. Process of claim 3 in which the temperature of reaction is from about 180 to 230 C.

5. Process of claim 3 in which the temperature of reaction is from about 100 to 160 C.

6. Process for preparing a barium alkyl phenate, comprising reacting barium sulfide, an alkyl phenol selected from the group consisting of monoalkyl phenols and dialkyl phenols and phenol in the presence of water at a temperature of about to about 160 C. until a barium alkyl phenate is produced, and recovering said barium alkyl phenate.

7. Process of claim 6 in which the temperature of reaction is from about to about C.

8. Process for preparing a barium alkyl phenate, comprising reacting 1 mole of barium sulfide, about 0.2 to 2.0 moles of phenol, and about 2 moles of an alkyl phenol selected from the group consisting of monoalkyl phenols and dialkyl phenols in the presence of about 0.8 to 3.5 moles of water, at a temperature of about 75 to 160 C., until barium a kyl phenate is produced, and recovering said barium alkyl phenate.

OTHER REFERENCES Stillson et al.: lour. Amer. Chem. Soc, vol. 67 (1945), 303-307 (5 pages). (Patent Ofiice Library.) 

1. PROCESS FOR PREPARING A BARIUM ALKYL PHENATE, COMPRISING REACTING BARIUM PHENATE WITH AN ALKYL PHENOL SELECTED FROM THE GROUP CONSISTING OF MONOALKYL PHENOLS AND DIALKYL PHENOLS AT A TEMPERATURE OF ABOUT 140* TO ABOUT 230*C. UNTIL A BARIUM ALKYL PHENATE IS PRODUCED, AND RECOVERING SAID BARIUM ALKYL PHENATE.
 8. PROCESS FOR PREPARING A BARIUM ALKYL PHENATE COMPRISING REACTING 1 MOLE OF BARIUM SULFIDE, ABOUT 0.2 TO 2.0 MOLES OF PHENOL, AND ABOUT 2 MOLES OF AN ALKYL PHENOLS SELECTED FROM THE GROUP CONSISTING OF MONOALKYL PHENOLS AND DIALKYL PHENOLS IN THE PRESENCE OF ABOUT 0.8 TO 3.5 MOLES OF WATER, AT A TEMPERATURE OF ABOUT 75* TO 160*C., UNTIL BARIUM ALKYL PHENATE IS PRODUCED, AND RECOVERING SAID BARIUM ALKYL PHENATE. 